Certain industrial components are often exposed to harsh environments. Some of these industrial components are coated in order to provide protection from these harsh environments and increase lifespan, reliability, or efficiency of the component.
As an example, electrical insulators used in high voltage power transmission lines are designed to maintain a minimum current discharge while operating outdoors. However, performance of the insulator degrades over time due to factors such as weather, moisture, corrosion, pollution, and so on. These factors can contaminate the surface of the insulator and can lead to the development of leakage currents that reduce the effectiveness of the insulator. These leakage currents can also cause arcing, which can further degrade the insulator surface. Eventually, a conductive path may form across the surface of the insulator and effectively short out the insulator, thereby nullifying its purpose.
One way of inhibiting degradation of electrical insulators is to coat the insulator with an elastomeric material such as a one component room temperature vulcanizable (RTV) silicone rubber. Such elastomeric coatings tend to enhance the outer surfaces of the insulator and can also improve insulator performance. For example, some coatings provide improved insulation, arc resistance, hydrophobicity, and resistance to other stresses imposed upon electrical insulators. Examples of such coatings are shown in the applicant's prior U.S. patents, specifically U.S. Pat. No. 6,833,407 issued Dec. 21, 2004; U.S. Pat. No. 6,437,039 issued Aug. 20, 2002; and U.S. Pat. No. 5,326,804 issued Jul. 5, 1994.
One problem is that the elastomeric coatings can be rather difficult to apply. For example, conventional high-pressure spraying techniques tend to have poor transfer efficiencies of 50% or lower, which results in vast amounts of wasted coating product.
Once an insulator is coated, it is then ready for installation. However, coating facilities are often located far away from the final installation site, possibly in other countries or on other continents. As such, transportation costs can represent a substantial expense when manufacturing and distributing coated insulators. Furthermore, the coatings applied to insulators can be damaged during transportation.
Another problem is that the coatings themselves may degrade over time while the insulator is in use, and at some point, it may be desirable to reapply the coating. However, as described above, the insulator might be deployed in remote areas far away from coating facilities, and transporting the insulator to a coating facility may be impractical.
One way of reapplying the coating is to manually re-coat the insulators in the field at a location closer to the insulator. Unfortunately, manual coating tends to provide an inconsistent quality coating and also tends to be inefficient. Furthermore, the environment and climate at different field locations tends to be variable. As such, it can be difficult to apply coatings with a consistent quality at various worksites located in different climates. Furthermore, in some cases, the climate of a particular field location may be unsuitable or unfavourable for re-coating the insulators. For example, the temperature or humidity of a particular field location may be outside optimal ranges for applying the particular coating.
In view of the above, there is a need for new and improved apparatus, systems, and methods of applying elastomeric coatings to industrial components such as electrical insulators.